It is not at all improbable that the first blades of grass that ever grew were in part grazed by some prehistoric plant-eating animal. All meat is a direct or indirect product of grass; therefore, grazing is not a new influence thrust suddenly into the environment of the plant but one that has existed throughout the ages. In the natural state, forces of nature operated to maintain a balance between animal life and the vegetation upon which it subsisted. No problems remained too long unsolved; no adjustments were too long delayed. If it had not been so, the ranges as we know them would have been eaten out of existence ages ago. To maintain abalance, the methods nature employed were direct and often harsh, consisting mainly of drought, reduction in birth rate, the predator and epidemic disease. With the accession of the stockmen to the ranges, a new influence was introduced which brought swift changes in the environment. Ranges were stocked with domestic animals, numbers of stock and their distribution were artificially regulated, the predator was practically eliminated, and disease was prevented. Drought alone remains uncontrolled and unpredictable. However, its force may be reduced and the impact eased by conservative stocking. The stockmen of the Southwest have originated many ingenious plans and systems of grazing in their efforts to minimize the ill effects of drought. The more promising of these practices have been incorporated into the designs of experiments conducted on the Jornada Experimental Range during the past quarter of a century.